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v4.10.11
  1#include <linux/cgroup.h>
  2#include <linux/slab.h>
  3#include <linux/percpu.h>
  4#include <linux/spinlock.h>
  5#include <linux/cpumask.h>
  6#include <linux/seq_file.h>
  7#include <linux/rcupdate.h>
  8#include <linux/kernel_stat.h>
  9#include <linux/err.h>
 10
 11#include "sched.h"
 12
 13/*
 14 * CPU accounting code for task groups.
 15 *
 16 * Based on the work by Paul Menage (menage@google.com) and Balbir Singh
 17 * (balbir@in.ibm.com).
 18 */
 
 
 19
 20/* Time spent by the tasks of the cpu accounting group executing in ... */
 21enum cpuacct_stat_index {
 22	CPUACCT_STAT_USER,	/* ... user mode */
 23	CPUACCT_STAT_SYSTEM,	/* ... kernel mode */
 24
 25	CPUACCT_STAT_NSTATS,
 26};
 27
 28static const char * const cpuacct_stat_desc[] = {
 29	[CPUACCT_STAT_USER] = "user",
 30	[CPUACCT_STAT_SYSTEM] = "system",
 31};
 32
 33struct cpuacct_usage {
 34	u64	usages[CPUACCT_STAT_NSTATS];
 35};
 36
 37/* track cpu usage of a group of tasks and its child groups */
 38struct cpuacct {
 39	struct cgroup_subsys_state css;
 40	/* cpuusage holds pointer to a u64-type object on every cpu */
 41	struct cpuacct_usage __percpu *cpuusage;
 42	struct kernel_cpustat __percpu *cpustat;
 43};
 44
 45static inline struct cpuacct *css_ca(struct cgroup_subsys_state *css)
 46{
 47	return css ? container_of(css, struct cpuacct, css) : NULL;
 48}
 49
 50/* return cpu accounting group to which this task belongs */
 51static inline struct cpuacct *task_ca(struct task_struct *tsk)
 52{
 53	return css_ca(task_css(tsk, cpuacct_cgrp_id));
 54}
 55
 56static inline struct cpuacct *parent_ca(struct cpuacct *ca)
 57{
 58	return css_ca(ca->css.parent);
 59}
 60
 61static DEFINE_PER_CPU(struct cpuacct_usage, root_cpuacct_cpuusage);
 62static struct cpuacct root_cpuacct = {
 63	.cpustat	= &kernel_cpustat,
 64	.cpuusage	= &root_cpuacct_cpuusage,
 65};
 66
 67/* create a new cpu accounting group */
 68static struct cgroup_subsys_state *
 69cpuacct_css_alloc(struct cgroup_subsys_state *parent_css)
 70{
 71	struct cpuacct *ca;
 72
 73	if (!parent_css)
 74		return &root_cpuacct.css;
 75
 76	ca = kzalloc(sizeof(*ca), GFP_KERNEL);
 77	if (!ca)
 78		goto out;
 79
 80	ca->cpuusage = alloc_percpu(struct cpuacct_usage);
 81	if (!ca->cpuusage)
 82		goto out_free_ca;
 83
 84	ca->cpustat = alloc_percpu(struct kernel_cpustat);
 85	if (!ca->cpustat)
 86		goto out_free_cpuusage;
 87
 88	return &ca->css;
 89
 90out_free_cpuusage:
 91	free_percpu(ca->cpuusage);
 92out_free_ca:
 93	kfree(ca);
 94out:
 95	return ERR_PTR(-ENOMEM);
 96}
 97
 98/* destroy an existing cpu accounting group */
 99static void cpuacct_css_free(struct cgroup_subsys_state *css)
100{
101	struct cpuacct *ca = css_ca(css);
102
103	free_percpu(ca->cpustat);
104	free_percpu(ca->cpuusage);
105	kfree(ca);
106}
107
108static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu,
109				 enum cpuacct_stat_index index)
110{
111	struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
112	u64 data;
113
114	/*
115	 * We allow index == CPUACCT_STAT_NSTATS here to read
116	 * the sum of suages.
117	 */
118	BUG_ON(index > CPUACCT_STAT_NSTATS);
119
120#ifndef CONFIG_64BIT
121	/*
122	 * Take rq->lock to make 64-bit read safe on 32-bit platforms.
123	 */
124	raw_spin_lock_irq(&cpu_rq(cpu)->lock);
125#endif
126
127	if (index == CPUACCT_STAT_NSTATS) {
128		int i = 0;
129
130		data = 0;
131		for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
132			data += cpuusage->usages[i];
133	} else {
134		data = cpuusage->usages[index];
135	}
136
137#ifndef CONFIG_64BIT
138	raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
139#endif
140
141	return data;
142}
143
144static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val)
145{
146	struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
147	int i;
148
149#ifndef CONFIG_64BIT
150	/*
151	 * Take rq->lock to make 64-bit write safe on 32-bit platforms.
152	 */
153	raw_spin_lock_irq(&cpu_rq(cpu)->lock);
154#endif
155
156	for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
157		cpuusage->usages[i] = val;
158
159#ifndef CONFIG_64BIT
160	raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
161#endif
162}
163
164/* return total cpu usage (in nanoseconds) of a group */
165static u64 __cpuusage_read(struct cgroup_subsys_state *css,
166			   enum cpuacct_stat_index index)
167{
168	struct cpuacct *ca = css_ca(css);
169	u64 totalcpuusage = 0;
170	int i;
171
172	for_each_possible_cpu(i)
173		totalcpuusage += cpuacct_cpuusage_read(ca, i, index);
174
175	return totalcpuusage;
176}
177
178static u64 cpuusage_user_read(struct cgroup_subsys_state *css,
179			      struct cftype *cft)
180{
181	return __cpuusage_read(css, CPUACCT_STAT_USER);
182}
183
184static u64 cpuusage_sys_read(struct cgroup_subsys_state *css,
185			     struct cftype *cft)
186{
187	return __cpuusage_read(css, CPUACCT_STAT_SYSTEM);
188}
189
190static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft)
191{
192	return __cpuusage_read(css, CPUACCT_STAT_NSTATS);
193}
194
195static int cpuusage_write(struct cgroup_subsys_state *css, struct cftype *cft,
196			  u64 val)
197{
198	struct cpuacct *ca = css_ca(css);
199	int cpu;
200
201	/*
202	 * Only allow '0' here to do a reset.
203	 */
204	if (val)
205		return -EINVAL;
206
207	for_each_possible_cpu(cpu)
208		cpuacct_cpuusage_write(ca, cpu, 0);
209
210	return 0;
211}
212
213static int __cpuacct_percpu_seq_show(struct seq_file *m,
214				     enum cpuacct_stat_index index)
215{
216	struct cpuacct *ca = css_ca(seq_css(m));
217	u64 percpu;
218	int i;
219
220	for_each_possible_cpu(i) {
221		percpu = cpuacct_cpuusage_read(ca, i, index);
222		seq_printf(m, "%llu ", (unsigned long long) percpu);
223	}
224	seq_printf(m, "\n");
225	return 0;
226}
227
228static int cpuacct_percpu_user_seq_show(struct seq_file *m, void *V)
229{
230	return __cpuacct_percpu_seq_show(m, CPUACCT_STAT_USER);
231}
232
233static int cpuacct_percpu_sys_seq_show(struct seq_file *m, void *V)
234{
235	return __cpuacct_percpu_seq_show(m, CPUACCT_STAT_SYSTEM);
236}
237
238static int cpuacct_percpu_seq_show(struct seq_file *m, void *V)
239{
240	return __cpuacct_percpu_seq_show(m, CPUACCT_STAT_NSTATS);
241}
242
243static int cpuacct_all_seq_show(struct seq_file *m, void *V)
244{
245	struct cpuacct *ca = css_ca(seq_css(m));
246	int index;
247	int cpu;
248
249	seq_puts(m, "cpu");
250	for (index = 0; index < CPUACCT_STAT_NSTATS; index++)
251		seq_printf(m, " %s", cpuacct_stat_desc[index]);
252	seq_puts(m, "\n");
253
254	for_each_possible_cpu(cpu) {
255		struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
256
257		seq_printf(m, "%d", cpu);
258
259		for (index = 0; index < CPUACCT_STAT_NSTATS; index++) {
260#ifndef CONFIG_64BIT
261			/*
262			 * Take rq->lock to make 64-bit read safe on 32-bit
263			 * platforms.
264			 */
265			raw_spin_lock_irq(&cpu_rq(cpu)->lock);
266#endif
267
268			seq_printf(m, " %llu", cpuusage->usages[index]);
269
270#ifndef CONFIG_64BIT
271			raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
272#endif
273		}
274		seq_puts(m, "\n");
275	}
276	return 0;
277}
278
279static int cpuacct_stats_show(struct seq_file *sf, void *v)
280{
281	struct cpuacct *ca = css_ca(seq_css(sf));
282	s64 val[CPUACCT_STAT_NSTATS];
283	int cpu;
284	int stat;
285
286	memset(val, 0, sizeof(val));
287	for_each_possible_cpu(cpu) {
288		u64 *cpustat = per_cpu_ptr(ca->cpustat, cpu)->cpustat;
289
290		val[CPUACCT_STAT_USER]   += cpustat[CPUTIME_USER];
291		val[CPUACCT_STAT_USER]   += cpustat[CPUTIME_NICE];
292		val[CPUACCT_STAT_SYSTEM] += cpustat[CPUTIME_SYSTEM];
293		val[CPUACCT_STAT_SYSTEM] += cpustat[CPUTIME_IRQ];
294		val[CPUACCT_STAT_SYSTEM] += cpustat[CPUTIME_SOFTIRQ];
295	}
296
297	for (stat = 0; stat < CPUACCT_STAT_NSTATS; stat++) {
298		seq_printf(sf, "%s %lld\n",
299			   cpuacct_stat_desc[stat],
300			   (long long)cputime64_to_clock_t(val[stat]));
301	}
302
303	return 0;
304}
305
306static struct cftype files[] = {
307	{
308		.name = "usage",
309		.read_u64 = cpuusage_read,
310		.write_u64 = cpuusage_write,
311	},
312	{
313		.name = "usage_user",
314		.read_u64 = cpuusage_user_read,
315	},
316	{
317		.name = "usage_sys",
318		.read_u64 = cpuusage_sys_read,
319	},
320	{
321		.name = "usage_percpu",
322		.seq_show = cpuacct_percpu_seq_show,
323	},
324	{
325		.name = "usage_percpu_user",
326		.seq_show = cpuacct_percpu_user_seq_show,
327	},
328	{
329		.name = "usage_percpu_sys",
330		.seq_show = cpuacct_percpu_sys_seq_show,
331	},
332	{
333		.name = "usage_all",
334		.seq_show = cpuacct_all_seq_show,
335	},
336	{
337		.name = "stat",
338		.seq_show = cpuacct_stats_show,
339	},
340	{ }	/* terminate */
341};
342
343/*
344 * charge this task's execution time to its accounting group.
345 *
346 * called with rq->lock held.
347 */
348void cpuacct_charge(struct task_struct *tsk, u64 cputime)
349{
350	struct cpuacct *ca;
351	int index = CPUACCT_STAT_SYSTEM;
352	struct pt_regs *regs = task_pt_regs(tsk);
353
354	if (regs && user_mode(regs))
355		index = CPUACCT_STAT_USER;
356
357	rcu_read_lock();
358
359	for (ca = task_ca(tsk); ca; ca = parent_ca(ca))
360		this_cpu_ptr(ca->cpuusage)->usages[index] += cputime;
361
362	rcu_read_unlock();
363}
364
365/*
366 * Add user/system time to cpuacct.
367 *
368 * Note: it's the caller that updates the account of the root cgroup.
369 */
370void cpuacct_account_field(struct task_struct *tsk, int index, u64 val)
371{
372	struct cpuacct *ca;
373
374	rcu_read_lock();
375	for (ca = task_ca(tsk); ca != &root_cpuacct; ca = parent_ca(ca))
376		this_cpu_ptr(ca->cpustat)->cpustat[index] += val;
377	rcu_read_unlock();
378}
379
380struct cgroup_subsys cpuacct_cgrp_subsys = {
381	.css_alloc	= cpuacct_css_alloc,
382	.css_free	= cpuacct_css_free,
383	.legacy_cftypes	= files,
384	.early_init	= true,
385};
v5.9
  1// SPDX-License-Identifier: GPL-2.0
 
 
 
 
 
 
 
 
 
 
 
  2/*
  3 * CPU accounting code for task groups.
  4 *
  5 * Based on the work by Paul Menage (menage@google.com) and Balbir Singh
  6 * (balbir@in.ibm.com).
  7 */
  8#include <asm/irq_regs.h>
  9#include "sched.h"
 10
 11/* Time spent by the tasks of the CPU accounting group executing in ... */
 12enum cpuacct_stat_index {
 13	CPUACCT_STAT_USER,	/* ... user mode */
 14	CPUACCT_STAT_SYSTEM,	/* ... kernel mode */
 15
 16	CPUACCT_STAT_NSTATS,
 17};
 18
 19static const char * const cpuacct_stat_desc[] = {
 20	[CPUACCT_STAT_USER] = "user",
 21	[CPUACCT_STAT_SYSTEM] = "system",
 22};
 23
 24struct cpuacct_usage {
 25	u64	usages[CPUACCT_STAT_NSTATS];
 26};
 27
 28/* track CPU usage of a group of tasks and its child groups */
 29struct cpuacct {
 30	struct cgroup_subsys_state	css;
 31	/* cpuusage holds pointer to a u64-type object on every CPU */
 32	struct cpuacct_usage __percpu	*cpuusage;
 33	struct kernel_cpustat __percpu	*cpustat;
 34};
 35
 36static inline struct cpuacct *css_ca(struct cgroup_subsys_state *css)
 37{
 38	return css ? container_of(css, struct cpuacct, css) : NULL;
 39}
 40
 41/* Return CPU accounting group to which this task belongs */
 42static inline struct cpuacct *task_ca(struct task_struct *tsk)
 43{
 44	return css_ca(task_css(tsk, cpuacct_cgrp_id));
 45}
 46
 47static inline struct cpuacct *parent_ca(struct cpuacct *ca)
 48{
 49	return css_ca(ca->css.parent);
 50}
 51
 52static DEFINE_PER_CPU(struct cpuacct_usage, root_cpuacct_cpuusage);
 53static struct cpuacct root_cpuacct = {
 54	.cpustat	= &kernel_cpustat,
 55	.cpuusage	= &root_cpuacct_cpuusage,
 56};
 57
 58/* Create a new CPU accounting group */
 59static struct cgroup_subsys_state *
 60cpuacct_css_alloc(struct cgroup_subsys_state *parent_css)
 61{
 62	struct cpuacct *ca;
 63
 64	if (!parent_css)
 65		return &root_cpuacct.css;
 66
 67	ca = kzalloc(sizeof(*ca), GFP_KERNEL);
 68	if (!ca)
 69		goto out;
 70
 71	ca->cpuusage = alloc_percpu(struct cpuacct_usage);
 72	if (!ca->cpuusage)
 73		goto out_free_ca;
 74
 75	ca->cpustat = alloc_percpu(struct kernel_cpustat);
 76	if (!ca->cpustat)
 77		goto out_free_cpuusage;
 78
 79	return &ca->css;
 80
 81out_free_cpuusage:
 82	free_percpu(ca->cpuusage);
 83out_free_ca:
 84	kfree(ca);
 85out:
 86	return ERR_PTR(-ENOMEM);
 87}
 88
 89/* Destroy an existing CPU accounting group */
 90static void cpuacct_css_free(struct cgroup_subsys_state *css)
 91{
 92	struct cpuacct *ca = css_ca(css);
 93
 94	free_percpu(ca->cpustat);
 95	free_percpu(ca->cpuusage);
 96	kfree(ca);
 97}
 98
 99static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu,
100				 enum cpuacct_stat_index index)
101{
102	struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
103	u64 data;
104
105	/*
106	 * We allow index == CPUACCT_STAT_NSTATS here to read
107	 * the sum of suages.
108	 */
109	BUG_ON(index > CPUACCT_STAT_NSTATS);
110
111#ifndef CONFIG_64BIT
112	/*
113	 * Take rq->lock to make 64-bit read safe on 32-bit platforms.
114	 */
115	raw_spin_lock_irq(&cpu_rq(cpu)->lock);
116#endif
117
118	if (index == CPUACCT_STAT_NSTATS) {
119		int i = 0;
120
121		data = 0;
122		for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
123			data += cpuusage->usages[i];
124	} else {
125		data = cpuusage->usages[index];
126	}
127
128#ifndef CONFIG_64BIT
129	raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
130#endif
131
132	return data;
133}
134
135static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val)
136{
137	struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
138	int i;
139
140#ifndef CONFIG_64BIT
141	/*
142	 * Take rq->lock to make 64-bit write safe on 32-bit platforms.
143	 */
144	raw_spin_lock_irq(&cpu_rq(cpu)->lock);
145#endif
146
147	for (i = 0; i < CPUACCT_STAT_NSTATS; i++)
148		cpuusage->usages[i] = val;
149
150#ifndef CONFIG_64BIT
151	raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
152#endif
153}
154
155/* Return total CPU usage (in nanoseconds) of a group */
156static u64 __cpuusage_read(struct cgroup_subsys_state *css,
157			   enum cpuacct_stat_index index)
158{
159	struct cpuacct *ca = css_ca(css);
160	u64 totalcpuusage = 0;
161	int i;
162
163	for_each_possible_cpu(i)
164		totalcpuusage += cpuacct_cpuusage_read(ca, i, index);
165
166	return totalcpuusage;
167}
168
169static u64 cpuusage_user_read(struct cgroup_subsys_state *css,
170			      struct cftype *cft)
171{
172	return __cpuusage_read(css, CPUACCT_STAT_USER);
173}
174
175static u64 cpuusage_sys_read(struct cgroup_subsys_state *css,
176			     struct cftype *cft)
177{
178	return __cpuusage_read(css, CPUACCT_STAT_SYSTEM);
179}
180
181static u64 cpuusage_read(struct cgroup_subsys_state *css, struct cftype *cft)
182{
183	return __cpuusage_read(css, CPUACCT_STAT_NSTATS);
184}
185
186static int cpuusage_write(struct cgroup_subsys_state *css, struct cftype *cft,
187			  u64 val)
188{
189	struct cpuacct *ca = css_ca(css);
190	int cpu;
191
192	/*
193	 * Only allow '0' here to do a reset.
194	 */
195	if (val)
196		return -EINVAL;
197
198	for_each_possible_cpu(cpu)
199		cpuacct_cpuusage_write(ca, cpu, 0);
200
201	return 0;
202}
203
204static int __cpuacct_percpu_seq_show(struct seq_file *m,
205				     enum cpuacct_stat_index index)
206{
207	struct cpuacct *ca = css_ca(seq_css(m));
208	u64 percpu;
209	int i;
210
211	for_each_possible_cpu(i) {
212		percpu = cpuacct_cpuusage_read(ca, i, index);
213		seq_printf(m, "%llu ", (unsigned long long) percpu);
214	}
215	seq_printf(m, "\n");
216	return 0;
217}
218
219static int cpuacct_percpu_user_seq_show(struct seq_file *m, void *V)
220{
221	return __cpuacct_percpu_seq_show(m, CPUACCT_STAT_USER);
222}
223
224static int cpuacct_percpu_sys_seq_show(struct seq_file *m, void *V)
225{
226	return __cpuacct_percpu_seq_show(m, CPUACCT_STAT_SYSTEM);
227}
228
229static int cpuacct_percpu_seq_show(struct seq_file *m, void *V)
230{
231	return __cpuacct_percpu_seq_show(m, CPUACCT_STAT_NSTATS);
232}
233
234static int cpuacct_all_seq_show(struct seq_file *m, void *V)
235{
236	struct cpuacct *ca = css_ca(seq_css(m));
237	int index;
238	int cpu;
239
240	seq_puts(m, "cpu");
241	for (index = 0; index < CPUACCT_STAT_NSTATS; index++)
242		seq_printf(m, " %s", cpuacct_stat_desc[index]);
243	seq_puts(m, "\n");
244
245	for_each_possible_cpu(cpu) {
246		struct cpuacct_usage *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
247
248		seq_printf(m, "%d", cpu);
249
250		for (index = 0; index < CPUACCT_STAT_NSTATS; index++) {
251#ifndef CONFIG_64BIT
252			/*
253			 * Take rq->lock to make 64-bit read safe on 32-bit
254			 * platforms.
255			 */
256			raw_spin_lock_irq(&cpu_rq(cpu)->lock);
257#endif
258
259			seq_printf(m, " %llu", cpuusage->usages[index]);
260
261#ifndef CONFIG_64BIT
262			raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
263#endif
264		}
265		seq_puts(m, "\n");
266	}
267	return 0;
268}
269
270static int cpuacct_stats_show(struct seq_file *sf, void *v)
271{
272	struct cpuacct *ca = css_ca(seq_css(sf));
273	s64 val[CPUACCT_STAT_NSTATS];
274	int cpu;
275	int stat;
276
277	memset(val, 0, sizeof(val));
278	for_each_possible_cpu(cpu) {
279		u64 *cpustat = per_cpu_ptr(ca->cpustat, cpu)->cpustat;
280
281		val[CPUACCT_STAT_USER]   += cpustat[CPUTIME_USER];
282		val[CPUACCT_STAT_USER]   += cpustat[CPUTIME_NICE];
283		val[CPUACCT_STAT_SYSTEM] += cpustat[CPUTIME_SYSTEM];
284		val[CPUACCT_STAT_SYSTEM] += cpustat[CPUTIME_IRQ];
285		val[CPUACCT_STAT_SYSTEM] += cpustat[CPUTIME_SOFTIRQ];
286	}
287
288	for (stat = 0; stat < CPUACCT_STAT_NSTATS; stat++) {
289		seq_printf(sf, "%s %lld\n",
290			   cpuacct_stat_desc[stat],
291			   (long long)nsec_to_clock_t(val[stat]));
292	}
293
294	return 0;
295}
296
297static struct cftype files[] = {
298	{
299		.name = "usage",
300		.read_u64 = cpuusage_read,
301		.write_u64 = cpuusage_write,
302	},
303	{
304		.name = "usage_user",
305		.read_u64 = cpuusage_user_read,
306	},
307	{
308		.name = "usage_sys",
309		.read_u64 = cpuusage_sys_read,
310	},
311	{
312		.name = "usage_percpu",
313		.seq_show = cpuacct_percpu_seq_show,
314	},
315	{
316		.name = "usage_percpu_user",
317		.seq_show = cpuacct_percpu_user_seq_show,
318	},
319	{
320		.name = "usage_percpu_sys",
321		.seq_show = cpuacct_percpu_sys_seq_show,
322	},
323	{
324		.name = "usage_all",
325		.seq_show = cpuacct_all_seq_show,
326	},
327	{
328		.name = "stat",
329		.seq_show = cpuacct_stats_show,
330	},
331	{ }	/* terminate */
332};
333
334/*
335 * charge this task's execution time to its accounting group.
336 *
337 * called with rq->lock held.
338 */
339void cpuacct_charge(struct task_struct *tsk, u64 cputime)
340{
341	struct cpuacct *ca;
342	int index = CPUACCT_STAT_SYSTEM;
343	struct pt_regs *regs = get_irq_regs() ? : task_pt_regs(tsk);
344
345	if (regs && user_mode(regs))
346		index = CPUACCT_STAT_USER;
347
348	rcu_read_lock();
349
350	for (ca = task_ca(tsk); ca; ca = parent_ca(ca))
351		__this_cpu_add(ca->cpuusage->usages[index], cputime);
352
353	rcu_read_unlock();
354}
355
356/*
357 * Add user/system time to cpuacct.
358 *
359 * Note: it's the caller that updates the account of the root cgroup.
360 */
361void cpuacct_account_field(struct task_struct *tsk, int index, u64 val)
362{
363	struct cpuacct *ca;
364
365	rcu_read_lock();
366	for (ca = task_ca(tsk); ca != &root_cpuacct; ca = parent_ca(ca))
367		__this_cpu_add(ca->cpustat->cpustat[index], val);
368	rcu_read_unlock();
369}
370
371struct cgroup_subsys cpuacct_cgrp_subsys = {
372	.css_alloc	= cpuacct_css_alloc,
373	.css_free	= cpuacct_css_free,
374	.legacy_cftypes	= files,
375	.early_init	= true,
376};